The invention relates to a method for recovering precious metals from electronic waste utilising biometallurgical techniques. In one aspect, a method of recovering one or more target metals from electronic waste, includes (a) removing at least a portion of non-target material from the electronic waste or grinding to a preselected size particle to give pre-processed electronic waste; (b) contacting the pre-processed electronic waste with a lixiviant such that at least a portion of the target metal(s) dissolve into the lixiviant to produce a pregnant solution; (c) contacting a microorganism with the pregnant solution such that at least a portion of the target metal(s) ions biosorb to the microorganism wherein the microorganism becomes metal laden and the pregnant solution becomes barren; (d) substantially separating the metal laden microorganism from the barren solution; and (e) recovery of the target metal(s) from the metal laden microorganism.

The present disclosure relates to processes for treating a coal associated material, e.g., acid mine drainage, while simultaneously recovering a high-grade rare earth preconcentrate suitable for extraction of commercially valuable rare earth oxides. Disclosed herein are methods for preparing a hydraulic pre-concentrate enriched in rare earth elements and critical minerals. Also disclosed herein are methods for preparing a pregnant leach solution from the disclosed hydraulic pre-concentrates. The present disclosure also relates to systems and plants for carrying out the disclosed processes. Also disclosed are compositions produced by the process disclosed herein in which the compositions comprise rare earth elements. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

The present disclosure relates to a method for treating an electromembrane process aqueous composition comprising sodium and/or potassium sulfate, said process comprising removing water from said electromembrane process aqueous composition under conditions suitable for substantially selectively precipitating sodium and/or potassium sulfate monohydrate.

The present disclosure relates to a method for treating an electromembrane process aqueous composition comprising sodium and/or potassium sulfate, said process comprising removing water from said electromembrane process aqueous composition under conditions suitable for substantially selectively precipitating sodium and/or potassium sulfate monohydrate.

Alkaline oxidation process for treating refractory sulfide ore or concentrate particles enriched in a metal to be recovered comprising stages in which refractory ore or concentrate particles are surface-oxidized in an alkaline oxidation step in alkaline liquid phase with calcium hydroxide forming an alkaline slurry, which slurry is thereafter mechanically activated to remove passivating coatings from the surface oxidized refractory ore particles.

A method of preparing metal hydroxides from industrial wastes or alkaline rocks is provided. The method comprise subjecting a mixture comprising a solvent and a solid substrate to a stimulus in order to leach a metal cation from the solid substrate into the solvent, thereby forming a solution comprising the metal cation in the solvent; and contacting the solution of comprising the metal cation with a cathode, thereby electrolytically precipitating the metal hydroxide from the solution. The stimulus may be chemical, mechanical, or both.

An ammonium complex system-based method for separating and purifying lead, zinc, cadmium, and copper, comprising the following steps: a zinc-containing raw material is leached using a leach solution to produce a leached solution; a filtrate and a filter residue are produced by filtration; the filtrate is mixed with metal lead to displace copper, undergoes a solid-liquid separation to produce a first separated liquid, is mixed with metal cadmium to displace lead, undergoes a solid-liquid separation to produce a second separated liquid, is mixed with metal zinc to displace cadmium, and undergoes a solid-liquid separation to produce a third separated liquid; and, the third separated liquid is electrolyzed to produce metal zinc, and an electrolytic solution is returned to the leaching step.

An ammonium complex system-based method for separating and purifying lead, zinc, cadmium, and copper, comprising the following steps: a zinc-containing raw material is leached using a leach solution to produce a leached solution; a filtrate and a filter residue are produced by filtration; the filtrate is mixed with metal lead to displace copper, undergoes a solid-liquid separation to produce a first separated liquid, is mixed with metal cadmium to displace lead, undergoes a solid-liquid separation to produce a second separated liquid, is mixed with metal zinc to displace cadmium, and undergoes a solid-liquid separation to produce a third separated liquid; and, the third separated liquid is electrolyzed to produce metal zinc, and an electrolytic solution is returned to the leaching step.

The present invention relates to the desulfurisation of lead-containing waste. In particular, the present invention relates to a method in which lead-containing waste is desulfurised to form a desulfurised lead-containing waste material which is suitable for recycling into lead or leady oxide. The method is particularly suitable for desulfurising lead-acid battery paste.

Provided is a slurry treatment apparatus includes: a treatment tank for performing any treatment of a solid-liquid reaction, a solid-gas reaction, a gas-liquid reaction, and solid-liquid separation on a slurry containing a metal or a metal compound; a first pipe; a second pipe; and a pump, in which one end of the first pipe has a suction opening for sucking the slurry from the treatment tank, the other end of the first pipe is connected to a suction port of the pump, one end of the second pipe is linked to a discharge port of the pump, the other end of the second pipe is connected to a microbubble generator, and the microbubble generator includes a throttle that throttles a flow of the slurry and a gas supply tube for supplying gas to the throttle, and supplies microbubbles to the slurry in the treatment tank.